Murfreesboro is a city in Pike County, Arkansas, United States. The population was 1,764 at the 2000 census. The city is the county seat of Pike County. Crater of Diamonds State Park is located just to the south. The crater is an eroded lamproite pipe where diamonds were discovered in 1906. 100,000 were found by 1933, and visitors to the park may still take away whatever they can find.
The guard cells surround each stoma in a plant cell. They regulate  the opening and closing of stomata to facilitate gas exchange and  control transpiration in plants.
If the Cell is a plant Cell, the Cell membrane  is inside of the Cell wall. It is semi-permeable, so water can move  freely into and out of the cell. Nutrient particles and gas  exchange occur where some molecules enter and waste products leave  through the Cell membrane. cell membrane protects a cell by controlling what substances go in and out of the cell. It lets good products go inside, but harmful products go out, which is basically prot â¦ ecting the cell.